Spraying equipment



Aprll 28, 1964 w. l.. sANBoRN ETAL 3,130,909

SPRAYING EQUIPMENT Filed Feb. 12, 1960 '7 sheets-sheet 1 Fig-1 f Mcm,

orneg April 28, 1964 w. L.. sANBoRN ETAL 3,130,909

SPRAYING EQUIPMENT Filed Feb. 12, 1960 7 sheets-sheet 2 Inventor 526furl J. Senn Inger 82B 182 Z 5g,- Mm, naww Miufaw *Hornegs April 28,1964 w. L. SANBORN ETAL 3,130,909

SPRAYING EQUIPMENT Filed Feb. 12, 1960 7 Sheets-Sheet 3 [1w ze mh @iF-se,

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Inven'ors wlliom I Sclrzborn for! J. enninger April 28, 1964 w. 1sANBoRN ETAL 3,130,909

SPRAYING EQUIPMENT Filed Feb. l2, 1960 7 Sheets-Sheet 4 EFSA: er

william I Sanbom Earl J. ennnger April 28, 1964 w. l.. sANBoRN ETAL3,130,909

SPRAYING EQUIPMENT Filed Feb. 12, 1960 7 Sheets-Sheet 5 Inventor'William L. Sanborn :Earl J. Sennner Mmm, H- Iiorneg April 28, 1964 w. L.sANBoRN ETAL 3,130,909

SPRAYING EQUIPMENT Filed Feb. l2, 1960 '7 Sheets-Sheet 6 InvenkonsWilliam. I... Sanbnrn Earl Jennnger April 28, 1964 w. 1 sANBoRN ETAL3,130,909

SPRAYING EQUIPMENT 7 Sheets-Sheet 7 Filed Feb. l2, 1960 SPRAY UNIT PowERTKE-oFF mw E R E T H o w T E N n D X R0 .ma R mA \.\RE

GEAR BOX Go'vERNo TRACTOR ENGINE nf r e eww n.mwm @Km0 Wf mmm@ ...mm m,:E w M ma United States Patent O International Telephone and TelegraphCorporation,v

New York, N.Y., a corporation of Maryland Filed Feb. 12, 1960, Ser. No.8,260 12 Claims. (Cl. 239-78) This invention relates to spraying oftrees, row crops and the like, and particularly to power-operated mobilespray apparatus wherein the spray material is carried into the desiredspray pattern by a high velocity carrier air blast.

In the spraying of crops, orchards and the like, the equipment hasgradually developed into an extremely large and costly form adapted tobe drawn through orchards, elds and the like by tractors and arranged toapply this spray material by an air blast that serves as a carrier forthe finely divided spray.

In practice, it has developed particularly in respect to the spraying oftrees in orchards, that the spraying apparatus is advanced or drawnthrough the space between the rows of trees at a constant speed in theneighborhood of l1/2 mph., and although this speed is variedconsiderably to meet varying conditions such as differences in the size,form or density of the trees, it is considered by many users to be thespeed best adapted to obtain proper coverage of the spray on the trees.In some instances speeds as low as one mile per hour have beenrecommended, and are used, but for illustrative purposes herein, thediscussion and examples will be confined to speeds of 11/2 miles perhour.

The spray materials that are used vary considerably in characteraccording to the purpose for which the materials are applied, so thatthe material may constitute mixture of water with spraying oil or liquidchemicals of different kinds, or may constitute mixtures of Water withpowdered chemicals. In the use of spray mixtures comprising water anddry powdered chemicals, it has been the general practice to use what arecalled dilute spraying mixtures, and it is upon the basis of such dilutemixtures that most of the agricultural and horticultural standards forspraying have been based. In such dilute mixtures it is customary tomix, for example, about two pounds of the spray chemical with onehundred gallons of water, and with these dilute mixtures, it has beenfound in prior sprayers that the material may be pressure-atomizedthrough nozzles that have spray orifices suiiiciently small to break theliquid spray material into reasonably ne drops or particles that may becarried to and distributed on the leaves and fruit of a tree by means ofa carrier air blast within which the several nozzles of the sprayingapparatus are disposed.

It has long been recognized that such dilute sprays call for the use ofan extremely large volume of water for each tree, and although initiallydistributed quite well on the leaves, limbs and fruit of a tree, thesedilute sprays will immediately start to run oit of the surfaces on whichit has been deposited so that by the time the water has evaporated, thecoating of chemical on the fruit, leaves or other parts of the tree isnot uniform. This run off or washdownj as it is termed in the fruitgrowing areas, has other objectionable effects, one of which is that nowork can be performed under the trees until the dripping of liquid hassubsided. This period may be as much as an hour in many instances,Another objectionable result is that a large proportion of the spraychemical is drained ofi of the surfaces of the tree and dropped to theground. This loss of chemical runs to about 30% in many instances, andrepresents a loss of money, and in addition,

3,130,909. Patented Apr. 28, 1964 such chemical often modifies thechemical composition of the soil under the trees so that correctivetreatments must be applied to the soil in order to restore the desiredfertility thereof.

The extremely high water requirements involved in the use of such dilutesprays is also considered to be objectionable and is quite costly inthat it increases the size and weight of the tanks that must be used inthe equipment, involves considerable loss of operating time for theequipment in refilling operations, and requires waterhauling equipmentand labor that constitute a major element of the cost of sprayingorchards and the like With such dilute sprays.

In the use of dilute sprays in the spraying of orchards, where the speedof the equipment is to be approximately 11/2 m.p.h., it is customary, asan example, to apply about one pound of chemical per minute, so thatwith a dilute spray that uses two pounds per one hundred gallons ofwater contained in the usual spray supply tank of five hundred galloncapacity, the entire contents of such ve hundred gallon tank isexhausted in about ten minutes of actual spraying time. It is thennecessary to refill the tank and to introduce and mix the chemicalsrequired before the spraying operation can be continued.

With prior equipment that has been used to apply dilute spray mixtures,the necessity for utilizing such a high proportion of Water in themixture has of course increased the amount of carrier air that isrequired to transport the atomized spray mixture from the spray nozzlesto the trees or crops, and this has necessitated the use of highcapacity, high discharge velocity fans and the like. It is customary toemploy air velocities in the carrier air of about seventy to ninetymiles per hour and to vary the direction of this carrier air so as toproduce twisting and turning movements of the leaves and fruit, and thiscauses spray coverage of all sides of the leaves and fruits. Withconventional spray equipment spraying dilute spray mixtures at the rateabove mentioned, the required fan output capacity has in many instances,been from seventy to eightly thousand cubic feet per minute. This hasimposed extremely great power requirements for such spraying apparatus,and in addition to this, the spray mixture has been fed to thepressure-atomization nozzles at extremely high pressures of from onehundred to six hundred pounds per square inch, so that pumps of anexpensive ltype were necessary and a great deal of power has beenrequired for pressurizinz the spray mixture.

Thus, the high power requirements, which made it necessary to employseparate engines for the fan and the pressure pumps, taken with the highcapacity of the fans employed in prior equipment, and the necessity forusing a large tank to contain the spray mixture, have resulted in priorspray equip-ment being extremely large and heavy, and the initial costas well as the operating cost of such prior equipment has been quiteburdensome.

The foregoing high costs and disadvantages of spraying orchards and thelike with dilute spray have long been recognized, and eiforts have beenmade for many years to use what have been called spray concentrates inwhich the ratio of chemical to water has been increased. While mentionis found in the literature of using spray concentrates that have up toeight times the proportion of powdered chemical as compared with dilutesprays, it has been found that where the concentrate goes as high asfour times the usual dilute spray ratio, the spraying results areunsatisfactory. Thus, with prior equipment, the increase in ratio ofchemical to water up to four times the accepted dilute spray ratio hasbeen accomplished only by a sacrifice in the effectiveness of thespraying operation. In other Words, with such a spray concentrate, thesmall spray orifices of the nozzles normally used for breaking up thedilute spray were quickly plugged up and rendered inoperative, and as aresult, larger nozzles were adopted andy the number of nozzles wasreduced materially so as to maintain the required pressure in thesystem. and limit the total delivery rate. Such larger nozzles, however,did not break up the spray material to a sufficient extent, andtherefore, the coverage of the tree surfaces was found to'be inadequate.

, These prior attempts to use spray concentrates have resulted in afurther difliculty in that the substitution of the larger nozzles toadapt a sprayer for use of spray concentrates makes it impossible to usethe refitted sprayer for dilute sprays, oil basedV sprays and the like,so that with prior equipment it has been necessary to spend many hourstime whenever it is desired to changeV from one type of spray materialto another.

As a result of the poor coverage that has been attained in the use of socalled spray concentrates as above described, and the difficulties ofchanging from one type of spray to another, it has been noted that therehas been a marked tendency for growers to discardr the use of sprayconcentrates and to go back to the use of dilute spray mixtures.

In view of the foregoing it is the primary object of the presentinvention to enable increased eiciency to be attained in sprayingorchards, row crops and the like and to reduce the operating costs andspraying time involved, and an object related to the foregoing is toenable the size, weight and cost of spraying equipment required for suchspraying operations.

Another important object of the invention is to enable owable spraymixtures of widely varying types and consistencies to be properly andeiciently applied by the same spray apparatus Without materialadjustment or reitting hereof, atnd a related object is to provide sprayapparatus that will handle With equal effectiveness, sprays that mayvary from a truly liquid form to a form that approached a thick,sludge-like slurry.

A further and important object of the present invention is to eliminatethe necessity for frequent reloading of spraying apparatus of theaforesaid type, and a related object is to reduce the water requirementsof spraying operations with the related reduction in the labor andequipment costs involved.

Another object of this invention is to enable spray mixtures to beemployed that are so highly concentrated as to be in the nature of asludge-like slurry, and to enable such highly concentrated mixtures tobe efficiently and uniformly applied to the surfaces of the trees orcrops that are being sprayed. A further and related object is to enabletrees and row crops to be sprayed with a quickdrying spraying mixture soas to eliminate the losses involved in washdown of the spray mixture andeliminate the necessity for subsequent treatment of the soil to restorethe required soil balance.

In spray apparatus of the kind heretofore used, the total delivery ratefrom the spray apparatus has been governed jointly by the flowability ofthe spray mixture, the size and number of spray discharge orifices, andthe pressure at which the spray material has been supplied to suchorifices, and any calibration of such prior apparatus may be disturbedby Variations in any one of these factors. In particular, it is foundthat the calibration of a spraying unit to meet a desired applicationrate has required the checking of the orifice sizes which vary due twear, and when there isy a change in the desired application rate, or achange in the amount of total discharge as related to time, thecalibration of the apparatus has been exceedingly difficult. It istherefore another important object of this invention to provide sprayapparatus which is in a practical sense independent of the variations ofthe size of the discharge orifices for all of the spray mixtures thatare to be used from a tnily liquid mixture to a sludge-like slurry suchas that Iabove mentioned, and related objects of this invention are toprovide such spray apparatus that may be quickly and easily calibratedor 4 checked for calibration when a dilferent discharge rate is to beestablished.

Another and more specic object of the present invention is to provide aspraying apparatus wherein the apparatus may be operated continuouslyfor long periods Without reloading, and to so construct and arrange thespraying apparatus that it is small in size so that it is adapted fortractor mouning on the usual load-supporting linkages of the tractor.

A further object is to provide such spraying apparatus wherein the powerrequirements are relatively small so that the apparatus may be drivenfrom the power take-oit shaft of a tractor upon which it is mounted.More specifically, it is an object to provide a spray apparatus of theaforesaid character wherein the spray material is accurately metered ata rate that is proportional to the rate of forward travel of the vehicleon which the spray apparatus is mounted, thus to assure that the spraymaterial will be applied evenly despite variations in rate of travel ofthe spraying vehicle.

It has been pointed out hereinbefore that in order to assure properapplication of the spray material to all sides and surfaces of theleaves, branches and fruit of an orchard, it is customary to vary thedirection of the air blast as the spraying apparatus moves through anorchard. In the past this has been accomplished by rocking or bendablevanes that serve as air directing means and which are operated at arelatively rapid rate as the movement of the spraying apparatusprogresses. Such vanes as used in the prior spraying units have beenrelatively complicated in their form and mounting and relatively diicultto operate at the speeds required, and it is therefore another importantobject of this invention to simplify the structure and operation of airdirecting vanes in spraying apparatus.

Other and further objects of the present invention will be apparent fromthe following description and claims, and are illustrated in theaccompanying drawings, which, by way of illustration, show preferredembodiments of the present invention and the principles thereof, andwhat is now considered to be the best mode in which to apply theseprinciples. Other embodiments of the invention embodying the same orequivalent principles may be used and structural changes may be made asdesired by those skilled in the art without departing from theinvention.

In the drawings:

FIG. 1 is a vertical central section taken from front to rear through aspraying apparatus embodying the features of the invention, the sprayingapparatus being shown schematically in association with a tractor uponwhich the spraying apparatus is mounted;

FIG. 2 is a front elevational view of the spraying apparatus, the viewbeing taken from the right in FIG. l;

FIG. 2A is a sectional view of the strainer that is included in theintake line of the metering pump;

FIG. 3 is a side elevational View of the spraying apparatus, the viewbeing taken from the opposite side of the apparatus;

FIG. 3A is a fragmentary view illustrating a different form of airdeflecting means;

FIG. 3B is a View taken substantially along the line 3B-3B of FIG. 3A;

FIG. 4 is a rear elevational view of the spraying apparatus, certainshroud plates being removed to show structure that is normallyconcealed;

FIG. 5 is a longitudinal sectional view through one of the spraynozzles;

FIG. 6 is a transverse sectional view taken substantially along the line6--6 of FIG. 5;

FIG. 7 is a plan view of the structure shown in FIG. 7;

FIG. 8 is an enlarged vertical sectional view of the metering pump unit;

FIG. 9 is an elevational view of the metering pump unit with certain ofthe parts removed so as to show the internal actuating and controlmechanism;

FIG. is a view of the air cylinder control means that is utilized forstarting and stopping the pumping unit; and

FIG. ll is a schematic view showing the way in which the spray materialis delivered at a rate that is constant with respect to the forward rateof travel of the tractor.

For purposes of disclosure the invention is herein illustrated in FIGS.1 to 1l as embodied in a spraying unit 20 which applies spray materialin the form of a thick, sludge-like slurry so as to have high outputcapacity, while at the same time being relatively small so that it maybe rear-mounted on a tractor 21 so as to be supported by means of theusual hydraulically actuated pickup links 22 of the tractor. The sprayunit 20 is thus supported on the tractor so that it may be readilymaneuvered through orchards, elds and the like, and the total powerrequirements for all of the elements of the spraying apparatus aresupplied by a drive that is connected to the power take-olf shaft of thetractor 2'1.

The spraying unit 20 comprises a tank 23 that is of a relatively shortcylindrical form, and rearwardly of the tank 23 a fan unit 24 is carriedon the tank 23 so that air drawn into the rear end of the fan unit 24may be discharged as a high Velocity carrier air blast generallyradially from the open edge portions of the fan outlet 24D.

Forwardly of the tank 23, frame structure is provided on the tankwhereby mounting of the various operating elements of the sprayingapparatus may be accomplished. Thus, the forward wall 23F of the tank 23forms a part of the mounting or frame structure of the sprayingapparatus 23, and a pair of vertically extended frame plates 25 areextended forwardly from the Wall 23F of the tank near the outer edges ofthe tank. The frame plates 25 provide mounting connections 22C for thelower pickup links 22, While a rearwardly extending bracket 22B isprovided so as to extend forwardly from the wall 23F for pivotalassociation with the upper mounting link 22. The frame plates 25 thuscooperate with the wall 2`3F in providing a mounting frame forsupporting the apparatus on a tractor, and also for other supporting andmounting functions, as will be described hereinafter. A supporting basefor the spray unit 20 is aforded by horizontal runners or skids 120located beneath the frame plates 2S and connected thereto and to thetank 23 by upwardly extending struts 1205.

The fan unit 24 has what may be termed the forward Vertical Wall of itshousing provided by the rear wall 23R of the tank 23, and on the wall23R, and substantially parallel but supported so as to be spacedrearwardly therefrom by spacer assemblies 26S, there is provided asecond vertical plate or wall 26 from which a cylindrical extension 27projects in a rearward direction. The space between the Wall 26 and thewall 23R constitutes the radial outlet 24D for the fan unit 24. Withinthe cylindrical extension 27, and extending forwardly into and throughthe tank 23, a clearance tube 28 is provided within which a drive shaft29 is mounted, and at its rear end the drive shaft 29 extends through abearing 29B, and a blade-type fan 31) is lixed to the rear end of theshaft 29 within the cylinder tube 27. The rear end of the tube 2S isrigidly supported by angular brace plates 128 that are radially disposedrelative to the tube 28 and are connected to the plate 23R. The rear endof the housing extension 27 has a projecting screen 31 mounted thereon,and when the fan 30 is rotated, its blades 36B draw air into the tubularhousing extension 27 and past a series of stationary radialair-directing blades 32 toward the radial discharge space between theplates 23R and 26. This air is discharged radially from that portion ofthe fan outlet 24D which has been uncovered. It might be pointed outthat along its bottom edge the fan casing is closed by a wall 124W thatextends between 6 the walls 23R and 26 and about the right side of theradial discharge area as shown in FIG. 4, so that the air discharge maybe conned to a particular arcuate section of the discharge outlet 24D.

At its forward end the shaft 29 is extended beyond the wall 23F and hasa multiple sprocket 37 xed thereon so that driving power may be appliedto the sprocket 37 for operating the fan 30. The particular way in whichdrive is applied to the sprocket 37 will be described hereinafter.

The fan 30 is arranged to discharge air from the fan housing at arelatively high velocity in the neighborhood of from 70 to 90 miles perhour, but under the present invention, where water-chemical ratio of thespray mixture is extremely low, the capacity of the fan 30 may berelatively low, as will be explained, so that a fan capacity of abouttwenty five thousand cubic feet per minute may be employed to accomplishspraying operations that have heretofore required a fan capacity of fromeighty thousand to ninety thousand cubic feet per minute.

Under the present invention the spray mixture that is contained in thetank 23 is air-atomized at a plurality of points along the air dischargeoutlet 24D of the fan by means of a plurality of nozzles 38 which aremounted on the plate 26 and extend forwardly as shown in FIG. 3 so thatthe discharge openings of the nozzles are located midway between theplates 23R and 26 and adjacent their outer edges. The nozzles 38 areshown in detail in FIGS, 5, 6 and 7 of the drawings, and it may beobserved that these nozzles 38 provide for quickly and easily changingthe size of the discharge openings thereof, and for quick and easycleaning when this is required.

Thus, each nozzle 38 comprises an elongated rod-like member 39 that hasa longitudinal bore 40 extended into one end thereof, and at said end,the member has a reduced screw-threaded nipple 39W formed thereon sothat the member 39 may be threaded into one of the cross arms of a Titting 41. The opposite cross arm of the T fitting has a plug member 42screwed therein, and this plug member has a relatively small tube 43extended therethrough, and into the passage 40 in an axial relation, aswill be described. The tube 43 is spaced from the wall of the bore 40 toprovide an annular passage about and concentric with the tube 43. Theplug 42 has a threaded cap 42C and packing 42P at its other end insurrounding relation to the tube 43 to provide a tight connectiontherebetween.

The other arm 41A of the T fitting constitutes an inlet for compressedair, while the tube 43 constitutes an inlet passage for spray mixturethat is fed to the nozzle 38, as will be described, and at the other orright hand end of the member 39, as shown in FIG. 5, means are providedfor air-atomizing the spray mixture and discharging the same laterallyfrom the nozzle in nely divided form and into and in the same generaldirection as the blast of carrier air. Thus, as shown in detail in FIGS.5 and 7, the right hand end of the member 39 has a relatively widetransverse slot 44 cut therein and to a depth beyond the central axis ofthe nozzle, and air and spray mixture are supplied to this slot as willbe described so that the slot 44 constitutes a mixing and atomizingchamber from which the atomized spray mixture is discharged radiallythrough a discharging opening in the form of a narrow slot 45. This slot45 is formed by milling or sawing in a replaceable sleeve 46 that may beslid endwise over the right hand end of the member 39 into a tightlysealed relationship with respect to a pair of O rings 47 that aremounted in appropriate annular slots in the member 39 on opposite sidesof the mixing chamber 44.

The air and the spray mixture enter the chamber 39 in such a relationthat the ow of pressure air passing the end of the tube 43 has anaspirating action of the spray mixture which is being constantlyadvanced in the tube 43 under a slight feeding pressure as will bedescribed. Thus, the right hand end of the bore 40 is slightly reducedas at 40K where the bore opens into the mixing chamber 44, and adischarge tip 43T in the form of a short length of smaller tubing isfixed in the end of the tube 43 and projects therefrom so that its righthand end is located about midway between the ends of the reduced bore orthroat 40K of the air passage.

With this nozzle arrangement, the spray mixture is Withdrawn from thetip 43T with an aspirating action, and the compressed air and the spraymixture are violently mixed within the chamber 44 so that the spraymixture is broken up into extremely fine particles and is discharged asa fan-like spray from the discharge slot 44.

Under the present invention the spray mixture from the tank 23 issupplied to the nozzles 38 by positive displacement metering means thatoperate at a rate that varies with the tractor speed so that the spraymixure will be evenly applied even though there may be substantialvariations in the speed of advancing movement of the tractor. Themetering action is timed with respect to the tractor speed by operatinga metering pump unit 50 through a drive connection from power take offshaft of the tractor as will be described. Under the present inventionthe metered iiow of spray material that is supplied by the pump unit 50to the nozzles 38 may be cut off or stopped at the will of the operatorso as to discontinue the spraying operation, as for example, when thespraying apparatus is passing between adjacent trees in an orchard, andthe means for attaining such control will be described in detailhereinafter.

The pumping unit 50, as shown herein, comprises a main casting 150, FIG.8, that has a central web 150W from which flanges 150F and 2501? extendrespectively, in reaward and forward directions as shown, particularly,in FIG. 8 of the drawings. The rearwardly extending flange 150G has acover plate 150C secured thereto so as to dene a gear chamber Withinwhich a gear 15tlG is mounted in xed relation on a rotatable centraldrive shaft 150S. The shaft 150s has a relatively small sprocket 51fixed on its outer or rear end as shown in FIGS. 1 and 8, and the shaft1508 is driven by a pinion 52 that is formed on the forward end of astub shaft 152 that is journalled in and projects through the rear coverplate 150C. At its rear end the stub shaft 152 has a multiple sprocket53 fixed thereon through which the pump unit 50 is operated or driven aswill be described hereinafter.

The forwardly projecting flange 2501J of the casting 150 provides aninternal chamber within which the pump driving and control mechanism ishoused, and this chamber is closed by a forward cover plate 250C. Withinthe drive chamber that is thus provided the forward end of the driveshaft 1508 has an eccentric pin or extension 54 upon which a ballbearing unit 54B is mounted so that the outer race of the ball bearingunit may serve as an operating means for driving a plurality of similarpositive displacement pumps Sti-1 to 56)-4, one such individual pumpbeing provided in this instance for each of the spray nozzles 38.

The pumps 50-1 to 50-4 are secured at intervals of 90 about the flange250F of the pump casting 150, and each of these pumps has a similarpositive displacement pumping means adapted to be operated by theeccentric 54 in the rotation of the drive shaft 1508. In the presentinstance the pump units 5%-1 to 55-4 are in the form of diaphragm pumps,each of which has a flexible diaphragm 56, the border of which isclamped between the opposed flat face of the individual pump body d-1for example, and the flange ZSF. These opposed faces are recessed sothat a pump chamber 57 is provided in the pump body and a clearancechamber 57C is provided in the ange ZSGF. The diaphragm 56 has a pushrod`156 associated therewith so as to project radially inwardly towardthe axis of the drive shaft 1508. An enlarged head 256 on each push rodis guided by portions of the casting 150 for radial movement, and aspring 356 urges the push rod in an inward radial direction, thespring356 being disposed about the rod between Ythe head 256 and the innersurface of the flange 250F. Hence, then each metering pump is urgedthrough its suction stroke by its spring 356, and is positively moved inan outward or discharge stroke by engagement of the out-er race of theball bearing unit 54B with the inner end of the head 256 or the push rodof the pump.

The spray mixture to be pumped is supplied to a common intake passage 58in the pump body 150, and each of the individual pumps has a supplypassage 158 extended from the passage 58 to the pumping chamber 57, andwithin this passage 158 an inlet check valve 258 is positioned. Anoutlet passage 358 extends from the pumping chamber 57 through the pumpbody and has an outlet valve 458 therein, and each of the individualpumps has its outlet passage 55S separately connected to its relatedspray nozzle 38, as will be described.

It has been pointed out that rotation of the drive shaft 1538 mayreciprocate or operate the push rods 156 of the four individual meteringpumps, and means are provided whereby the pumping strokes of these pumpsmay be adjusted so that the desired spray coverage will be attained. Themeans for adjusting the stroke of the pump push rods 156 is in thisinstance also employed for stopping the pumping operation of the severalpumps, as for example, when the discharge of spray material is to bediscontinued between trees. Such control means includes a four-lobe cam59 fixed on the inner rear end of a shaft 159 that extends through thecover plate 250C on the same axis as the drive shaft 1508. The cam 59has four identical and gradually sloping cam lobes 59C, as indicated inFIG. 9, and these cam lobes are adapted to engage respectively withcontrol pins 256C that extend from the respective heads 256 of the pushrods. As will be evident in FIG. 9 of the drawings, the rotation of thecam 59 in a counterclockwise direction will cause the high points of theseveral cam lobes 59C to engage the related pins 256C so as to urge theheads 256 radially outwardly and beyond the range of the rotatingeccentric drive member. Thus, when the pumping action is to be stopped,the cam 59 is rotated just slightly less than in a counterclockwisedirection from the position shown in FIG. 9. It should be pointed outthat the slope of the several cam lobes 59C is quite gradual, and bysetting the cam 59 at some intermediate position, the extent of inwardradial movement of the push rods 156 may be controlled so that a shorterpump stroke is attained in each rotation of the drive shaft 1508. Thisaffords an output adjustment for the pump 50, and this output adjustmentis attained by limiting the extent of clockwise movement of the controlshaft 159.

The control shaft 159 is arranged so that it is normally urged in acounterclockwise direction, FIG. 5, to what may be termed a pump-offposition, and this is accomplished by an operating arm 159A that isfixed on the shaft 159 and has a spring 159S acting thereon to urge theshaft 159 in a counterclockwise direction to its pumpoff position.

Under the present invention the control shaft 159 is adapted to beshifted in a clockwise direction toward a pump-on position by means thatare under control of an operator seated on the tractor. This meansincludes a piston and cylinder unit 359 having the piston rod 359Pthereof connected by a pin and slot connection with the end of the arm159A. Pressure air is supplied through a hose 459 to the left hand endof the piston and cylinder unit 359 as viewed in FIG. 10, and in thisline a manual control valve 459V is located, this valve normally beingmounted on the tractor adjacent the drivers seat.

When the operator wants the pump to start its pumping operation, air issupplied to the piston and cylinder unit 359, and normally the cylinderwould rock the cam 59 clockwise to substantially the position shown inFIG. 9. However, if a shorter pump stroke is desired, this may beattained by limiting the stroke of the piston rod 359, and for thispurpose, a control rod 559 mounted on and parallel to the piston rodextends slidably through a stationary bracket 559B, and nuts 559N on therod serve as an adjustable means for limiting the piston stroke, therebyto enable the stroke of the pumps to be adjusted.

The adjustment that is thus afforded is a common or simultaneousadjustment of the stroke of all of the four individual pumps, but insome instances, it is found that it may be desirable to feed the supplymixture at different rates to one or more of the nozzles 38. Foraccomplishing such individual adjustment, individual adjusting means areprovided for varying the pumping stroke of the several individual pumps.Thus, as shown in FIG. 8, cup-like members 60 are mounted on rotativestuds 60S thatextend through the cover plate 256C so that one of thecup-like members extends loosely over the end of each of the pins 256C.The cup-like members 69 are mounted eccentrically on the stud 66S sothat by rotative setting or adjustment of the stud 66S, the inward orsuction stroke of the releated push rod 156 may be variably limited.Thus, certain of the pumps may operate with pumping strokes determinedby the cam 59, and one or more of the pumps may be adjusted to a shorterstroke by the studs 66S. Lock nuts 69N are provided on the studs 60S forsecuring the same in any desired adjusted position.

The output or discharge passages 358 of the several pumps Sil-1 to StB-have individual delivery hoses 6I connected thereto, and these hoses areextended upwardly from the pump as shown in FIGS. 1 and 2, and throughthe wall of a clearance tube 23T that is extended through the upperportion of the tank 23 and substantially across the outlet opening 24D.The hoses 61 extend from the tube 23T through the wall 26, and along therear side of the plate 26 to the spray liquid connections 43 of therespective nozzles 3S. The tube 23T serves additional functions as willbe pointed out hereinafter.

Compressed air for air-atomizing the spray mixture in the nozzles 33 isprovided from a supply tank 66 that is formed in part by the left-handframe plate 25, as viewed in FIG. 2. Thus, the tank 66 has its righthand Wall, as Viewed in FIG. 2, formed by the adjacent frame plate 25,While a suitable arcuate plate and a forward plate cooperate with thewall 23F of the tank 23 to complete the tank 66 which has an inletopening 66F therein so that the tank may be partially filled withspraying oil L that is used as a lubricating oil for purposes that willappear hereinafter. A sight glass 66G is preferably provided for thetank 66, as shown in FIG. 2.

A similar tank 166 is provided at the right hand side of the apparatus,as shown in FIG. 2, this tank being provided for containing a supply offresh water to be used in flushing the pump 50 and the nozzles 38, aswill be described. The tank 166 has a filling opening 166F and a sightgauge 166G.

Compressed air is supplied to the tank 66 to maintain a predeterminedpressure level therein by means of an air compressor 68 that is mountedon the left hand frame plate 25, as viewed in FIG. 2. The compressor 68is preferably cooled by air derived from the fan 24, and for thispurpose the sleeve 23T has an air inlet 123A cut therein so as to faceradially inwardly of the fan outlet 24D. The air entering the inlet 123Apasses forwardly through the tube 23T and then passes laterally from thetube 23T through a iiexible hose 128, the other end of which is fixed inposition to discharge air over the compressor 68. The outlet of the aircompressor 68 discharges to the tank 66. An outlet stub 69 from theupper portion of the tank 66 supplies compressed air through a hose 69Hto the forward end of a pipe 69? that extends rearwardly through theclearance tube 23T and is connected at its rear end to a manifold pipe70 that extends arcuately around the outside of the fan housing 27 asshown in FIGS. 1 and 4. Hose connections 71 are provided from themanifold 70 to the arms 41A of the respective nozzles 38. It might bepointed out that during operation of the present apparatus, compressedair flows constantly from the tank 66 through the manifold 70 and to theseveral nozzles 38, and discharge of spray material from the nozzles 38is controlled quickly and easily by cutting off the supply of spraymixture under control of the valve 459V as hereinbefore described.

The supply of spray mixture from the tank 23 to the metering pump 5@ is,under the present invention, related with a spray mixing and circulatingsystem which includes a centrifugal pump 75 that is mounted on the righthand frame plate 25 by means of an adjustable pump bracket 75B, and thispump is driven constantly as will be hereinafter described. Thecentrifugal pump 75 has an inlet connection including a hose 76 that isconnected to a three-way valve 77. One port 77F of the valve 77constitutes an inlet port which in one setting of the Valve 77 may servethrough a suitable hose connection for loading the tank 23 with water,and when thus connected the water is drawn through the valve 77 and theintake hose 76 to the pump 75 from which it is discharged through anoutput line 79 into the tank 23. It is important to note that the outputline 79 includes a hose 79H which is connected to a horizontal dischargeportion 79D that opens into the right hand side of the tank 23, asviewed in FIG. 2. The pipe 79D is relatively close to the bottom of thetank, and the discharge of water or spray mixture from the pipe '79Dserves to produce a mixing or agitating action which maintains the spraymixture in a uniform condition, as will be discussed hereinafter.

After filling of the tank 23 with water has been completed, thethree-way valve 77 is adjusted so that the inlet connection or port 77Fis closed, and a connection is established between the hose '76 andhorizontal intake pipe 83. The pipe Sii extends horizontally into thelower portion of the tank 23, as indicated in FIG. 1, and terminates inspaced relation to the pipe 79D. The spray chemical in the form of apowder may be introduced into the tank 23 through a large coveredfilling opening 223, and this may be done either before or after thewater is introduced. The pumping action serves, of course, to agitatethe chemical and mix the same with the water, and since the pump 75 isoperating constantly during spraying operation of the apparatus, thereis a continual and relatively high volume circulation of the liquidspray mixture through the pumping system, and the mixture is constantlyagitated and maintained in a uniform condition by the discharge ofliquid from the pipe 79D into the lower portion of the tank.

The spray mixture is supplied to the metering pump 50 by an intakeconnection 81 that is extended from the passage 58 of the pump 50through three-way valve 81V to a fitting 82 that is interposed in thedischarge line 79 of the pump 75. The metering pump 50 is of relativelysmall capacity as compared with the capacity of the pump 75, so that avery small proportion of the mixture flowing through the pipe iswithdrawn by the pump 50, and it may be noted that this spray mixturethat is withdrawn has just passed through this centrifugal pump 75 sothat it has been subjected to a final mixing operation just before it isdelivered to the metering pump.

Under the present invention the fitting 82 is embodied as aself-cleaning strainer and the details thereof are illustrated in FIG.2A of the drawings. Thus, it will be noted that the fitting 82 is in theform of an elongatedl cylindrical member that has threaded bores 82Bextended into its opposite ends axially thereof, and between these boresthe fitting 82 is internally enlarged to provide a clearance chamber 82Cthat is of a substantially greater diameter than the threaded openings82B. The valve 81V that is included in the supply line to the meteringpump 50 is mounted on the fitting 82 midway between its ends by means ofa nipple 81N that is threaded into a radial bore 81B so that the supplyline 81 for the metering pump 50 connects with the chamber 82C.

Within the iitting 82 a cylinder wire mesh sleeve 182 is positioned sothat its opposite ends are located snugly within and are supported andcentered on the adjacent portions of the two bores 82B, and at one endof the litting the valve 89 has a laterally extending nipple 79Nthreaded into the bore 82B so as to engage the adjacent end of the wirescreen or sleeve 182. At the other end of the fitting 82, an elbow '79Ethat forms a part of the return line 79D is similarly threaded into theother bore 82B so as to engage the other end of the wire sleeve 182. Thefitting 82 thus provides a strainer through which the spray mixture mustpass in an outwardly radial direction in order to reach the spray line81 of the metering pump, and hence the spray mixture that is to bemetered is properly strained.

The strainer that is thus provided is self-cleaning in character, for asabove pointed out, the metering pump Sti withdraws but a smallproportion of the mixture that is tiowing through the centrifugal pump'75. Hence, there is a constant and relatively large liow of spraymixture longitudinally through the fitting 82 and within the screenedsleeve 182, and as a result of this constant and relatively high volumeand high speed iiow, any lumps of spray chemical, or other material,that may have been stopped by the screen 182 are flushed in a right handdirection through the iitting 82 and back into the tank 23 so as to besubjected to a further mixing operation. This assures proper operationof the metering pump t).

The three-way valve 81V is normally set to connect the fitting 82 withthe pump supply passage or hose 81, but in its other setting, the pumpinlet hose 81 is connected to a water supply hose 181 that extends fromthe other port of the valve 81V to the lower portion of the Water tank166. Thus, the water in the tank 166 may be utilized for flushing andcleaning the pump and the nozzles 38, and in addition, the Calibratingoperations that may be necessary with respect to the pump 5t) may beaccomplished by pumping Water from the tank 166.

As shown herein, the outlet 24D of the fan 24 has been restrictedthrough the application of a cover plate 124D along one side of the fanoutlet so that the fan outlet 24D is open only along one side thereof,and with this arrangement the spraying apparatus 20 is adapted forspraying trees along only one side of the path of travel of the sprayingapparatus. Means are provided in the open portions of the fan outlet forvarying the direction and intensity of the air blast periodically atrelatively short intervals so that the desired swaying and turningmovement of the leaves and fruits of the trees may be induced by thevarying action of the air blast thereon. This swaying and turning isrecognized as being desirable to assure spray-coating of all sides ofthe fruits, leaves and limbs of a tree in the course of a sprayingoperation.

Under the present invention, the periodic deflection of the air blast isaccomplished by air-directing vanes or plates that are simple in bothstructure and operation, and two different forms of air deflecting meansutilizing the same basic mounting and mode of actuation are provided forobtaining a somewhat diiierent pattern of air deection in the respectivetypes. Thus, in FIGS. l to 4, a plurality of rotatable transverse shafts85 are mounted relatively close to the outer edge of the plate 26 in anequally spaced relationship so as to extend through the plate 26 andpartially across the outlet 24D. These shafts 85 are rotated in unisonduring operation of the spraying unit, and each shaft has a deflectorplate 86 fixed thereon so as to project equally on opposite sides of theshaft and in a plane that is relatively close to and parallel to theaxis of the shaft. The plates 86 are narrower than the outlet 24D so asto be spaced from the plates 26 and 23R. Thus, as the shafts 85 arerotated,

12 the angle of the deflector 86 will be' gradually changed' so that thepath of the air blast will be varied, and at times when adjacent deectorplates are disposed substantially parallel to the plane of the outlet24D, the intensity of the last in that area will be materially reduced.

The deflector plates 86, as shown in FlGS. l to 4, are effective only tochange the direction of the air blast in a vertical plane that is normalto the line of travel of the spray unit, but in some instances it isdesirable also to vary the direction of the air blast in what may betermed a front to rear direction with respect to the path of travel ofthe spraying unit. Such control of the air blast may be attained by thealternative deiiector plate structure illustrated in FIGS. 3A and 3B ofthe drawings.

Thus, in FIGS. 3A and 3B, each deflector unit has a rotatable shaft 85which Icorresponds in form and location with the shafts 85 shown inFiGS. 3 and 4, but in this instance, a circular detiector plate 186 ismounted on the shaft y185 midway between the plates 26 and 23R in such`a relation that the shaft 8'5 extends through the center of the plate1486 with the plate supported eat an acute angle to the axis of theshaft 85. The deiiector plate 185 thus has the characteristics of alwobble plate, which in rotation of the shaft S5, will progressivelychange the direction of the Iair blast so \as to direct the air blast atcertain times in an upward direction, at other times in a downwarddirection and at still `other times to directions that extend at eithera forward angle or Ia rearward angle with respect to the path of travelof the spraying apparatus.

The deliector pilates 85 and 186 may be employed -selectively accordingto the kind of iair blast variations that are desired, and in the use ofeither 'deflector plate arrangement, the operation thereof, land theperiodic changes of direction of air blast, are accomplished bycontinuous rotation of the mounting shafts 85 in one direction.

All of the shafts 85 of the deiiector system are driven in unison, andas herein shown, each Is'haft has a sprocket 87 thereon just rearwardlyof the plate 26. These sprockets 87 are connected by an endless chain 88which has an idler pulley 89 associated therewith. Near the shaft S5that is locate-d in the uppermost position on the unit, as shown in FIG.4, a drive sprocket 89 is meshed with the chain 88, and the sprocket 89is iixed on the rear end of a drive shaft 185, as shown in FIG. l. Theshaft 185 extends forwardly through the lupper portion of the tank 23within a olearance tube 185T, and dni-Ve sprocket 189 is fixed'thereonjust forwardly of the forward wall of the tank 23 so that drive may be-tnansmitted to the shaft 185, as will be described. A removable shroud127, FIG. l, is extended from the outer edge of the plate 26 to the rearedge of the fan housing 27 so as to house and protect the deliectordrive, the material supply hoses and the air supply lines.

It has been pointed out hereinabove rthat |all of the power consumingelements of the present spraying apparatus are driven from la commonpower source, and to enable tlhis to be done, the power input Kshafts ofthe compressor 68, the metering pump 58 and the centrifugal pump 75' arearranged parallel to the axis of the fan 29 and have multiple drivesprockets 53 of the metering pump, 37 of the fan, 68S of the compressor,and 75S of the pump 75 located in a common vertical plane. An end-lesschain ydrive is provided in the present instance by a plurality ofparallel endless roller chains 90 that are extended about the sprocket37 on the right hand side thereof as shown in FIG. 2, and then upwardlyat an angle and about the left hand side of the sprocket 68S of thecompressor. The ohain 90 then extends to the right under and inengagement with sprocket 53 of the metering pump, and then over anddownwardly about the sprocket 75S of the pump 75 to relatively largesprocket SlS that is mounted on the forward' end of la jaclcshaft 91substantially below the sprocket 37. 'Iihe mounting running clutch 91Cso as to prevent undue stress on the drive chain when the tractor-mo-tor is stopped. The chains 90 then extend upwardly to the sprocket37. The jack-shaft 91 is mounted by means of bearings 91B that aredisposed within a clearance tube 91T that extends through the tank 23 asshown in FIG. 1. An endless chain 93 is extended around the sprocket 51and the sprocket 181 for driving the air deliector system.

The common drive that is thus provided, may within the purview of thepresent invention, be driven from any suitable power source, but wherethe spraying apparatus is adapted `for tractor mounting on the liftinglinks 22 of a tractor, the common drive system is actuated from thepower take-ofi shaft 95 of the tractor lchat is shown diagrammaticallyin FIG. 1l. The power take-off shaft 95 is connected to the jack-shaft91 by means of a telescoping, universal jointed drive shaft |195, FIGS.1 and ll.

It has been pointed out that the tank 66 contains a supply of liquidlubricant L which is maintained under reiatively high pressure by thecompressed air in the top portion vof the tank 66, and this lubricant isutilized to supply continuous lubrication to the elements of the drive.The oil that is used in the present instance is -a tree spraying oil ofthe kind usually used for scale control. It has been found that such Oilhas good lubricating qualities. A small trace of such -oil is carried bythe compressed air to the nozzles 38, and by use of spraying toil, it ispossible to attain the 'desired lubrication in a simple way while at thesame time assuring that there will be no damage to the trees such aswould result from the use of ordinary oil.

As shown in FIG. 2, a supply pipe 96S is extended from a lower portionof the tank 66 to the compressor, and an -oil mist line 96M is extendedfrom the compressor through a mist control valve 96V so as to dischargeonto the drive chains 9i).

The spraying unit 20 as herein shown is relatively small, as will beevident from the comparison `of the unit with the size of lthe wheelsIof the tractor 21, and the tank 2.3 has a relatively small volumetriccapacity. ln the present instance the tank capacity is substantiallyninety gallons, and the fan unit 24F that has been ernployed has anoutput of substantially 25,000 cubic feet per minute at a velocity ofabout eighty miles per hour.

As hereinabove pointed out the spraying apparatus of the presentinvention enables the spraying mixture to be so highly concentrated so`as to be in the nature of a sludge-like slurry so that for attainingthe same degree of application of chemical to the trees or crops, thetotal volumetric output of the nozzles 38 is relatively small ascompared to prior spray-ing apparatus of this general kind.

In the use of prior spraying apparatus it has been pointed out that withthe normal dilute spray mixture, the chemical is mixed in the ratio oftwo pounds of chemical to one hundred gallons of water, so that in thelive hundred gallon tank of the prior spraying apparatus, there wascontained but a total of ten pounds of chemical. Even if prior apparatuswere used with the concentrated mixtures that have heretofore beenproposed, the ratio of chemical to water in the spray was relativelysmall. As an example, in a concentrate that was lfour times the normaldilute ratio, the total chemical content in the ve hundred gallon tankwould be about forty pounds. In contrast to the prior sprayingapparatus, it may be pointed out that Iwith the apparatus of the presentinvention, as described herein, it is possible to use as much as 300pounds of powdered spray chemical in the ninety gallon tank. Thisquantity or weight of powdered spray chemical actually occupies aconsiderable portion of the volume of the tank 23, and the balance ofthe tank is filled with water which may amount to about fifty-fivegallons.

, It has been pointed out that usually the spraying apparatus isadvanced through an orchard at about a rate of 11/2 miles per hour, andat this rate it is customary to apply the spray in such volume that thechemical will be discharged at a rate of about one pound per minute.Operating at such a rate of spray application, with three hundred poundsof spray chemical in the tank 23, the spraying apparatus of thisinvention may operate continuously for a period of three hundredminutes. Applying chemical at the same rate with the dilute spray abovedescribed, it would be possible to operate for only ten minutes from afive hundred gallon tank. Hence the time lost in filling operations hasbeen materially reduced by the apparatus of the present invention, andof course the waste of water and labor and equipment in hauling theexcess water has been eliminated. Moreover, the weight of spray mixturethat must be carried to the trees by the air blast has been greatlyreduced so as to enable the output capacity of the fan to be minimized.

The use of the extremely thick or sludge-like spray mixture by theapparatus of the present invention produces a uniform coating on theleaves, fruit and the like, and this coating, as it is deposited,contains so little water that it takes but one minute or so for thespray to dry. This quick drying action of course eliminates the drippingor run-down that has been experienced with prior spraying apparatus, andenables work in an orchard to be resumed almost immediately aftercompletion of the spraying operation.

The present apparatus discharges the spray material at a rate thatvaries with the rate of forward movement of the vehicle, and this ofcourse assures uniform application of spray material. The meteringaction in the present instance is attained through the drive of themetering pump from the power take-off shaft of the tractor, FIG. 11, andin this connection it may be pointed out that during a sprayingoperation the speed of the tractor engine 96 is usually controlled bygovernor 97, FIG. 1l, and the speed of the power take-off shaft 95 withrelation to the speed of forward travel of the tractor is determined bythe particular gear in which drive gear box 98 of the tractor is set.Actually the power take-off shaft 95 usually is driven through asettable gear box 99 from the tractor engine 98, and this, however, hasbeen found to be unobjectionable because a particular user will operatethe tractor 21 in the same drive gear and with the same setting of thegear box 99 to the power take-olf shaft throughout the entire sprayingoperation.

The highly concentrated spray mixture is of course put under a feedingpressure by the metering pump, and this pressure is relatively small,being in the neighborhood of twenty pounds per square inch under normalcircumstances so as to be about the same as the pressure of thecompressed air that is used. The spray mixture is advanced to eachnozzle 38, and as it leaves the end tip of the material passage, it isaspirated into the mixing or atomizing chamber by compressed air thatows at a high rate through the surrounding throat 40R. In practice, ithas been found that the compressed air should be at a pressure ofapproximately twenty pounds per square inch, and at this pressure thespray mixture is violently agitated and broken up while it is in theatomizing charnber 46, and is discharged through the slot 45 as anarcuate fan-like spray, the arcuate extent of which is determined by thelength of the slot 45, and the base thickness and the particle size ofsuch spray is determined by the Width of the slot 45.

It will be observed that the slot 45 of each nozzle 38 is disposedsubstantially in a vertical plane that is located midway between thefront and rear sides of the air blast that is discharged from thedischarge opening 24D, and the spray from each nozzle 38 divergesangularly in front and rear directions as it moves away from thedischarge slot 45. The nely divided spray is thus well distributedthroughout a substantial cross sectional area of l the carrier air blastso that it may be picked up and-carried by the blast to the surfaces ofthe trees.

The direction and intensity of the air blast is varied by the constantlyrotating delectorV plates 86 and this varying control of the air blastcauses the air blast to be directed at varying angles upwardly,horizontally and somewhat downwardly as the rotation of the delectorplates 86 progresses. Moreover, it will be observed that the deilectorplates 36 are arranged so as to be substantially parallel to each otherat all times, and being disposed with their parallel axes arcuatelyarranged about the discharge opening 24D, certain of the adjacentdeilector plates 86 will at certain times in each cycle of operation beeiective to substantially block limited areas of the discharge opening.At this time other portions of the discharge openings 24D are eitherfully or partially open so that there will be progressive variations ofthe direction as well as variations in the intensity or velocity of theair blast, and this results in the desired twisting and turning of theleaves, fruit and the like by the air blast.

When the direction of the air blast is to be varied to some extent in afront to rear direction with respect to the line of travel of thespraying apparatus, the wobble plate type of deliector plate 136 may beemployed, and this produces up and down variations of the direction ofthe air blast, and in addition varies a direction of the air blastforwardly and rearwardly as the movement of the apparatus progresses.

In the operation of the present apparatus, the spray oil L inthecompressed air tank 66 serves as a constant pressure lubricant sourcethrough which lubricant is fed continuously to the chains 90. It is alsoimportant to note that the pump 75 operates constantly to circulate andmix the spray material, and this circulation takes place at a rate thatis far in excess of the pumping rate of the metering pump 50. Themetering pump 50 is supplied by withdrawing a part of the flowing orcirculating spray mixture from the circulating system so that the spraymaterial that is fed to the nozzle is fully and properly mixed. Thecirculating pump 75 of course serves for loading the tank 23 with waterand for initially mixing the water and the spray chemical.

With the spraying apparatus of the present invention it has been foundthat the spraying of the orchard or the like may be accomplished in muchless time than with prior apparatus, due primarily to the long periodsover which the apparatus may be used without reloading, and because ofits small size and power requirements the initial cost of `the equipmentis much less than with prior equipment of the same work-performingcapacity. The elimination of wash down has `of course reduced the dryingtime so that work can ybe resumed in -an orchard soon after the sprayingthereof, and the eiimination of wash down has resulted in a saving ofmoney that would otherwise be expended in soil restoration. The stavingin cost of chemicals due to the elimination of wash down, plus thesaving in labor that results from the reduced need for water, hasproduced a net saving of about 30% in spraying operations performed withthe apparatus of the present invention.

The spray apparatus that has thus been provided under this invention isof such a character that spray material of widely varying consistenciesmay be properly distributed without material alternation or reiitting ofthe apparatus. The air atomizing spray heads that are utilized underthis invention operate with equal facility on conventional liquid sprayssuch as dilute spray mixture or spraying oils, or on extremely heavy andsludge-like spray mixtures.

In the event that a user does desire to change the size and shape of thedischarge openings of the sprays, it is only necessary for such user toremove and replace the sleeves 46 from the nozzles, and this may be donemerely by pulling the sleeves endwise ofi of the body of the nozzle.

Similarly, the sleeves 46 may be removed when 75 16 it is foundnecessary to clean the discharge openings 4S, but in practice, it hasbeen found that the spray discharge openings S may in most instances becleaned while the sleeve 46 is in place, this being accomplished bymerely inserting a thin coin or knife blade through the slot 4-5.

The present apparatus is `also of great advantage -in that it lendsitself to rapid and accurate calibration where this is desired. Thus themain drive of the apparatus may be connected through a particular gearbox setting of the power take-ott shaft, the valve 31V may be set sothat water will be pumped from the tank 166, and the output hose 6i ofone of the metering pumps may be disconnected so that the output of thatmetering pump may be discharged into a measuring container for a fixedtime period to check the volumetric output of the pump. Thus theperformance may be checked for any particular driving speed of theapparatus and for a particular stroke adjustment of the individual pumpwithout material loss of time and without loss of spray material. Thesight glass 166G has a scale thereon showing the contents of the watertank 166, and such scale may also be used in Calibrating the pump unit56 as to total output.

In the foregoing description the operation of the present sprayingapparatus has been set forth in connection with the spraying of treeswhere the fan is utilized in connection with the air deilectors toproduce a high volume, high velocity air blast for carrying the spraymixture to the trees, but it should be recognized that in certainsituations the use of an air blast is not required, and is in factundesirable, as for example in the spraying of grape vines. The presentapparatus operates to eveninly and electively spray grape vines and thelike without the use of the air blast that is provided by the fan, andwhen such a spraying operation is to be carried out, the fan 30 may beremoved or otherwise disabled so that the spray from the nozzles 38 willbe directed toward the vines, but will not be subjected to the usual airblast.

Thus, while preferred embodiments of the invention have been illustratedherein, it is to be understood that changes and variations may be madeby those skilled in the art without departing from the spirit and scopeof the appending claims.

We claim:

1. In a spraying apparatus, a fan unit having an air outlet throughwhich high velocity carrier air blast is discharged, an air atomizationspray nozzle disposed at said outlet in the path of the air blast andhaving a spray opening discharging in the direction of movement of saidcarrier air blast, and a constantly driven air compressor, a pressuretank for containing a supply of oil and to which the output of saidcompressor is supplied to provide a compressed air source and a sourceof oii under pressure, means'connected to said tank for supplyingcompressed air to the nozzle, a pump for feeding liquid spray to thenozzle under pressure and at a predetermined rate, drive means for saidpump and said compressor, and lubricating means for said compressorsupplied with oil under pressure from said tank.

2. In a spraying unit for orchards and the like, a tank having verticalfront and rear walls, a fan unit mounted on said rear wall' and having acylindrical housing with a rear end lair intake Iand terminating in anoutwardly projecting housing wail at its forward end spaced rearwardlyfrom and cooperating with said rear Wall of the tank to dene a radialair outlet, a fan mounted in said housing and having a fan shaftextended forwardly through said tank, cover plates closing portions ofthe radial air outlet to limit the air discharge to a selected portionori such outlet, a plurality of rotatable ideiiector shafts extendedacross said selected portion of the outlet in spaced relation to eachother and parallel to said fan shaft, spray nozzles disposedintermediate at least certain of said deector shafts, deflector bladesfixed on each of said deflector shafts, frame members on said front wailof the tank and having connecting means thereon for supporting the uniton the lifting links of a tractor, means including a drive shaft mountedon said front wall of the tank for feeding spray material from the tankand discharging the same from said nozzles, and a main operating shaftconnected to all of the aforesaid shafts for driving the same andadapted t be connected to and driven by the power take-off shaft of atractor on which the unit is supported.

3. In a spraying unit for orchards and the like, a tank having verticalfront and rear walls, a fan unit mounted on said rear wall and having acylindrical housing with a rear end air intake and terminating in anoutwardly projecting housing wall at its forward end spaced rearwardly Ifrom and cooperating with said rear wall of the tank to define a radialair outlet, a fan mounted in said housing and having a fan shaftextended forwardly through said tank, cover plates closing portions ofthe radial air outlet to limit the air discharge to a selected portionof such outlet, a plurality of air deflectors extended across saidselected portion of the outlet in spaced relation to each other, meansincluding an operating shaft parallel to said fan shaft for operatingsaid deiiectors to vary the direction of said air blast, spray nozzlesdisposed intermediate at least certain of said deflectors, frame memberson said front wall of the tank and having connecting means thereon forsupporting the unit on the lifting links of a tractor, means including adrive shaft mounted on said front wall of the tank for feeding spraymaterial from the tank and discharging the same from said nozzles, and amain operating shaft connected to all of the aforesaid shafts fordriving the same and adapted to be connected to and driven by the powertake-o" shaft of a tractor on which the unit is supported.

4. In a spraying unit for orchards and the like, a tank having verticalfront and rear walls, a fan unit mounted on said rear wall and having arear end air intake and a radial air outlet, a fan mounted in saidhousing and having a fan `shaft extended forwardly through said tank,cover plates closing portions of the radial air outlet to limit the airdischarge to a selected portion of such outlet, a plurality of movableair deflector plates extended across said selected portion of the outletin spaced relation to each other and operating means for said deilectorplates including an operating shaft, spray nozzles disposed intermediateat least certain of said deilector plates, frame members on said frontwall of the tank and having connecting means thereon for supporting theunit on the lifting links of a tractor, means including a drive shaftmounted on said front wall of the tank for feeding spray material fromthe tank and discharging the same from said nozzles, and a mainoperating shaft connected to all of the aforesaid shafts for driving thesame and adapted to be connected to and driven by the power take-offshaft of a tractor on which the unit is supported.

5. In a mobile spraying unit, a tank having vertical front and rearwalls, a fan unit mounted on said rear wall and having a rear end airintake and a radial air outlet, a fan mounted in said housing and havinga fan shaft extended forwardly through said tank, cover plates closingportions of the radial air outlet to limit the air discharge to aselected portion of such outlet, a plurality of movable air dellectorplates disposed in the path of the air blast in spaced relation to eachother and operating means for said deflector plates including anoperating shaft, air atomization spray nozzles disposed in the path ofthe air blast, frame members on said front wall of the tank and havingconnecting means thereon for supporting the unit on the lifting links ofa tractor, positive displacement pump means including a drive shaftmounted on said front Wall of the tank for feeding spray material fromthe tank to said nozzles, an air compressor for supplying compressed airto said nozzles and including a drive shaft, and a main operating shaftconnected to all of the aforesaid shafts for driving the same andadapted to be connected l to and driven by the power take-olf shaft of atractor on which the unit is supported.

6. In a mobile spraying apparatus, a spray material supply tank and afan housing permanently associated with each other to provide a unitaryassembly, said fan housing providing a rear air intake and a radial airdischarge opening from which a high velocity carrier air blast may bedischarged, a fan in said housing having forwardly projecting fan shaft,air atomization spray nozzles each having an internal mixing chamber ona spray opening therefrom for discharging spray material into thecarrier air blast, a mounting frame on the forward side of the assembly,movable deflector means at the radial air discharge opening for varyingthe discharge direction of air passing therethrough, means including adrive shaft mounted on the frame for moving said del'lector means,positive displacement metering pump means, including a drive shaft,mounted on said frame for feeding spray material from the tank to themixing chambers of said nozzles, an air compressor, including a driveshaft, and mounted on said frame for supplying pressure air to themixing chambers of said nozzles, means for directing a portion of theair from said fan onto said compressor for cooling the same, means onthe frame for connecting the same to the lifting arms of a tractor, anda main drive on the frame connected to said shafts and adapted to beconnected to and driven by the power take-off shaft of such a tractor.

7. ln a spraying apparatus, a frame and a wheeled vehicle upon which theframe is mounted, a tank and a fan unit supported on the frame, said fanunit having an air outlet through which high velocity carrier air blastis discharged, a plurality of air atomization spray nozzles disposed inspaced relation at said outlet in the path of the air blast and having aspray opening discharge in the direction of movement of said carrier airblast, means for supplying compressed air to said nozzles, a pluralityof positive displacement metering means operated in timed relation tothe movement of the vehicle for feeding spray mixture to the nozzles,each of said metering means being allocated to one of said spray nozzlesto supply mixture thereto, and means for simultaneously adjusting theoutput rate of the several metering means, and other means forindependently adjusting the output rate of at least certain of saidindependent metering means to enable spray mixture to be delivered tothe several spray nozzles at different rates.

8. In a spraying apparatus, .a frame and a wheeled vehicle upon whichthe frame is mounted, a tank and a fan unit supported on the frame, saidfan unit having an 'air outlet through which high velocity carrier airblast is discharged, a plurality of air fatomization spray nozzlesdisposed in spaced relation at said outlet in the path of the lair blastand having a spray opening discharge in the direction of movement ofsaid carrier air blast, means for supplying compressed air to saidnozzles, a plurality of positive displacement pumping units operated intimed relation to the movement of the vehicle for feeding spray mixtureto the nozzles, each of said pumping units being 'allocated Ito :one ofsaid spray nozzles, yand means for independently adjusting the outputrate of said independent pumping units to enable spray mixture to bedelivered to the several spray nozzles at different rates.

9. In a spraying apparatus, a lf-rame and a wheeled vehicle upon whichthe frame is mounted, a tank and a fan unit supported on the frame, saidfan unit having an air outlet through which high velocity carrier airblast is discharged, a plurality yof lair atomization spray nozzlesdisposed in spaced relation at said `outlet in Ithe path of the airblast :and having spray openings discharging in the direction of thecarrier air blast, means for supplying pressure air to the respectivenozzles, land ndependently adjustable metering means operated in timedrelation to the ladvancing movement of the vehicle for i9 feeding spraymixture `to the nozzles at relatively different rates to the respectivespray nozzles.

10. In a spraying apparatus, a fan unit having :an air outlet throughwhich a high velocity carrier lair blast is discharged in the directionof the object to be sprayed, a spray nozzle disposed at 4said outlet inthe path of the carrier .air blast, -said nozzle having a nozzle bodywith an :internal mixing chamber therein and said body having a spr-ayopening from said chamber through which material may pass from saidchamber in said general direction of movement of the air blast, saidspray opening bein-g restricted substantially in area as compared withthe ladjacent portions of said chamber, an air compressor and an'associated pressure air tank for providing a source of compressed airat a predetermined pressure, a supply tank for containing highlyconcentrated spray mixture `and having a constantly operating mixingmeans associ-ated therewith for maintaining the spray mixture inuniformly mixed condition, la volumetric metering pump for lfeedingspray mixture fro-m the supply tank and discharging such mixture Vintosaid mixing chamber Iat a point remote from said spray opening and atsubstantially said predetermined pressure, means for feeding compressedair from said pressure air tank and discharging such compressed iair atsubstantially said predetermined pressure for intermixture with .thespray mixture kat substantially said predetermined pressure within saidmixing chamber for sudden expansion upon passing lthrough said sprayopening to air-atomize the spray mint-ure, and constantly shifted vanesin the path of said air blast adjacent said nozzle for producing lateraloscillation of the carrier blast.

l1. In a spraying apparatus, a fan unit having an air outlet throughwhich a high velocity carrier air blast is discharged in the directionof the object to be sprayed, a spray nozzle disposed at said outlet inthe path of the carrier air blast, said nozzle having a nozzle body withan internal mixing chamber therein and said body having a spray openingfrom said chamber through which material may passfrom said chamber insaid general direction of movement of they air blast, said spray openingbeing restricted substantially in area as compared-with the adjacentportions of said chamber, an air compressor and an associated pressureair tank for providing a source of compressed air at a predeterminedpressure, a supply tank for containing highly concentrated spray mixtureand having a constantly operating mixing means associated therewith formaintaining the spray mixture in uniformly mixed condition, a volumetricmetering pump for feeding spray mixture from the supply tank anddischarging such mixture into said mixing chamber at a point remote fromsaid spray opening and at substantially said predetermined pressure,means for constantly feeding compressed air from said pressure air tankand discharging such compressed air at substantially said predeterimnedpressure for intermixture with the spray mixture at substantially saidpredetermined pressure within said mixing chamber and for suddenexpansion upon passing through said spray opening to air-atomize thespray mixture as it enters said air blast, constantly shifted vanes inthe path of said air blast adjacent said nozzle for producing lateraloscillation of the carrier blast, and manually controlled cutoff meansfor interrupting the feeding of the spray mixture when the sprayingaction is to be interrupted.

12. In a spraying unit for orchards and the like, a tank having verticalfront and rear walls, a fan unit mounted on said rear wall and having acylindrical housing with a rear end air intake and terminating in anoutwardly projecting housing wall at its forward end and spacedrearwardly from and coperating with said rear Wall of the 'tank todeiine a radial air outlet area, a fan mounted in said housing, meansclosing portions of the radial air outlet area to confine the airdischarge to a nal air outlet of limited size, a plurality of shiftabledetlector plates extended across said iinal air outlet in spacedrelation to each other, spray nozzles disposed intermediate at leastcertain of said deector plates, shifting means for shifting saiddeilector plates, frame members on said front Wall of the tank andhaving connecting means thereon for supporting the unit on the liftinglinks of a tractor, means including a drive shaft mounted on said frontwall of the tank for feeding spray material from the tank anddischarging the samefrom said nozzles, and a main operating shaftconnected in driving relation to said fan and said shifting means fordriving the same and adapted to be connected to and driven by the powertakeoff shaft of a tractor on which the unit is supported.

References Cited in the le of this patent UNITED STATES PATENTS1,989,696 Kelley Feb. 5, 1935 2,012,973 Parker Sept. 3, 1935 2,551,789Copley May 8, 1951 2,593,096 Brusdal Apr. 15, 1952 2,659,625 GramothyNov. 17, 1953 2,674,494 Matteson et al. Apr. 6, 1954 2,707,847 AnlikerMay 10, 1955 2,757,800 Kucera Aug. 7, 1956 2,768,859 Patterson Oct. 30,1956 2,886,249 Sidlow May 12, 1959 2,975,543 Funk Mar. 21, 1961 FOREIGNPATENTS 588,592 Great Britain May 28, 1947

9. IN A SPRAYING APPARATUS, A FRAME AND A WHEELED VEHICLE UPON WHICH THEFRAME IS MOUNTED, A TANK AND A FAN UNIT SUPPORTED ON THE FRAME, SAID FANUNIT HAVING AN AIR OUTLET THROUGH WHICH HIGH VELOCITY CARRIER AIR BLASTIS DISCHARGED, A PLURALITY OF AIR ATOMIZATION SPRAY NOZZLES DISPOSED INSPACED RELATION AT SAID OUTLET IN THE PATH OF THE AIR BLAST AND HAVINGSPRAY OPENINGS DISCHARGING IN THE DIRECTION OF THE CARRIER AIR BLAST,MEANS FOR SUPPLYING PRESSURE AIR TO THE RESPECTIVE NOZZLES, ANDINDEPENDENTLY ADJUSTABLE METERING MEANS OPERATED IN TIMED RELATION TOTHE ADVANCING MOVEMENT OF THE VEHICLE FOR FEEDING SPRAY MIXTURE TO THENOZZLES AT RELATIVELY DIFFERENT RATES TO THE RESPECTIVE SPRAY NOZZLES.